package com.sky.aspect;


import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.time.LocalDateTime;

/**
 * 自定义切面类，实现公共字段自动填充处理逻辑
 */
@Aspect
@Component
@Slf4j
public class AutoFillAspect {
    //定义切入点
    @Pointcut("execution(* com.sky.mapper.*.*(..)) && @annotation(com.sky.annotation.AutoFill)")
    public void autoFillPointcut(){

    }
    //定义通知(前置通知),在通知中进行公共字段的赋值
    @Before("autoFillPointcut()")
    public void autoFill(JoinPoint joinPoint) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
        log.info("开始进行公共字段的自动填充...");

        //获取到当前被拦截的方法上的数据库操作类型
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();//获得方法签名对象
        AutoFill autoFill = signature.getMethod().getAnnotation(AutoFill.class);//获得方法上的注解对象
        OperationType operationType = autoFill.value();

        //获取到当前被拦截的方法的参数--实体对象
        Object[] args = joinPoint.getArgs();
        //防止空指针异常
        if (args.length == 0 || args == null){
        return;
        }
        Object entity = args[0];

        //准备赋值的数据
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();


        //根据当前不同的操作类型，为对应的属性通过反射来赋值
        if (operationType ==OperationType.INSERT){
            //需要为四个公共字段赋值
            try {
                //规范代码书写  可以将拼写的字符串更改为AutoFillConstant.SET_CREATE_TIME等规定好的常量，防止编写代码过程中因拼写错误导致的代码报错
                //Method setCreateTime = entity.getClass().getDeclaredMethod("setCreateTime", LocalDateTime.class);
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                //Method setCreateUser = entity.getClass().getDeclaredMethod("setCreateUser", Long.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                //Method setUpdateTime = entity.getClass().getDeclaredMethod("setUpdateTime", LocalDateTime.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                //Method setUpdateUser = entity.getClass().getDeclaredMethod("setUpdateUser", Long.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);
                //通过反射为对象属性赋值
                setCreateTime.invoke(entity,now);
                setCreateUser.invoke(entity,currentId);
                setUpdateTime.invoke(entity,now);
                setUpdateUser.invoke(entity,currentId);
            } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
                throw new RuntimeException(e);
            }
        }else if(operationType == OperationType.UPDATE){
            //需要为两个公共字段赋值
            //Method setUpdateTime = entity.getClass().getDeclaredMethod("setUpdateTime", LocalDateTime.class);
            Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
            //Method setUpdateUser = entity.getClass().getDeclaredMethod("setUpdateUser", Long.class);
            Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);
            setUpdateUser.invoke(entity,currentId);
            setUpdateTime.invoke(entity,now);
        }
    }
}
